U.S. patent application number 12/494379 was filed with the patent office on 2010-06-03 for method for conversion of atmospheric carbon dioxide into useful materials.
Invention is credited to Thomas Proger KAPLAN.
Application Number | 20100137457 12/494379 |
Document ID | / |
Family ID | 42223392 |
Filed Date | 2010-06-03 |
United States Patent
Application |
20100137457 |
Kind Code |
A1 |
KAPLAN; Thomas Proger |
June 3, 2010 |
METHOD FOR CONVERSION OF ATMOSPHERIC CARBON DIOXIDE INTO USEFUL
MATERIALS
Abstract
A method for converting carbon dioxide in a gaseous environment,
including air into useful materials by use of renewable energy
sources which comprises: (1) extracting carbon dioxide from a
gaseous source using a sorbent such as sodium hydroxide, calcium
hydroxide, or potassium hydroxide; (2) utilizing wind power, solar
power, or other renewable energy sources to regenerate said sorbent
by membrane cell electrolysis or other similar method,
simultaneously producing hydrogen (H.sub.2) gas; (3) releasing
carbon dioxide from said sorbent; and (4) utilizing the Fischer
Tropsch process, Mobil process, ICI process, or related or similar
processes to convert carbon oxides to a hydrocarbon concomittantly
with or after effecting the reverse water-gas shift reaction to
convert said CO.sub.2 and H.sub.2 gas into carbon monoxide for
reaction in said Fischer Tropsch process, Mobil process or ICI
process.
Inventors: |
KAPLAN; Thomas Proger; (New
York, NY) |
Correspondence
Address: |
LADAS & PARRY LLP
26 WEST 61ST STREET
NEW YORK
NY
10023
US
|
Family ID: |
42223392 |
Appl. No.: |
12/494379 |
Filed: |
June 30, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61077321 |
Jul 1, 2008 |
|
|
|
Current U.S.
Class: |
518/702 |
Current CPC
Class: |
C25B 1/34 20130101; Y02P
20/00 20151101; C07C 29/1516 20130101; Y02P 20/50 20151101; C10G
2/30 20130101; Y02P 20/133 20151101; C07C 29/1516 20130101; C07C
31/04 20130101 |
Class at
Publication: |
518/702 |
International
Class: |
C07C 27/06 20060101
C07C027/06 |
Claims
1. A method for producing hydrocarbons from ambient carbon dioxide
which comprises: (1) extracting carbon dioxide from a gaseous
source using a sorbent such as sodium hydroxide, calcium hydroxide,
or potassium hydroxide; (2) utilizing wind power, solar power, or
other renewable energy sources to regenerate said sorbent by
membrane cell electrolysis or other similar method, simultaneously
producing hydrogen (H.sub.2) gas; (3) releasing carbon dioxide from
said sorbent; and (4) utilizing the Fischer Tropsch process, Mobil
process, ICI process, or related or similar processes to convert
carbon oxides to a hydrocarbon concomittantly with or after
effecting the reverse water-gas shift reaction to convert said
CO.sub.2 and H.sub.2 gas into carbon monoxide for reaction in said
Fischer Tropsch process, Mobil process or ICI process.
2. The method of claim 1, wherein CO.sub.2 is extracted from
ambient air.
3. The method as claimed in claim 2, wherein said extraction is
effected by passively passing such air over a CO.sub.2
adsorbent.
4. The method as claimed in claim 3, wherein said absorbent is an
aqueous solution of an alkali metal or alkaline earth metal
hydroxide.
5. The method as claimed in claim 2, wherein exposing sorbent
covered surfaces to air streams where the airflow is kept laminar,
or close to the laminar regime
6. The method as claimed in claim 1, wherein CO.sub.2 is released
from the absorbent by contact with a halogen.
7. The method as claimed in claim 6, wherein carbon dioxide is
captured in said absorbent as a Na.sub.2CO.sub.3 solution and is
released by bubbling a gaseous chlorine, through the solution.
8. The method of claim 7, wherein sodium chloride solution formed
by reaction of chlorine with the said solution is electrolysed to
produce sodium hydroxide.
9. The method of claim 8, wherein sodium hydroxide produced is
recycled for adsorption of carbon dioxide.
10. The method of claim 8, wherein said electrolysis is effected by
membrane cell electrolysis.
11. The method of claim 1, wherein carbon dioxide released from
said sorbent is at least partially converted to carbon
monoxide.
12. The method of claim 11, wherein said conversion is effected by
the reverse shift water gas reaction.
13. The method of claim 11, wherein carbon oxides are converted to
hydrocarbons by reaction with hydrogen in the Fischer Tropsch
reaction.
14. The method of claim 11, wherein carbon oxides are converted to
methanol.
15. The method of claim 11, wherein carbon oxides are converted to
hydrocarbons by reaction with hydrogen to produce methanol which is
then converted to hydrocarbon.
16. The method of claim 17, wherein carbon oxides are converted to
hydrocarbons by reaction with hydrogen in the ICI reaction.
17. The method of converting ambient carbon dioxide into a
hydrocarbon which comprises absorbing carbon dioxide from air into
a sodium hydroxide solution to form sodium carbonate, releasing
carbon dioxide from said solution by passing chlorine gas through
it to produce aqueous sodium chloride, subjecting the carbon
dioxide so released to a reverse shift water gas reaction and
reaction with hydrogen to produce a hydrocarbon and subjecting said
aqueous sodium chloride to electrolysys to produce sodium hydroxide
and chlorine and recycling at least some of said sodium hydroxide
and chlorine for reuse in the method.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a method for converting
carbon dioxide existing in a gaseous environment, including air,
into useful materials by use of renewable energy sources.
[0002] Removal of carbon dioxide from air by use of soda lime, for
example in submarines, has been known since the 1940's. Other
techniques include absorption in monoethanolamine and use of
membranes. However, use of recovered carbon dioxide seems to have
been limited. As noted in Quimica Nova vol. 22 n. 2 Sao Paulo
March/April 1999, recovered carbon dioxide has been injected into
oil wells to enhance oil recovery. Other uses of carbon dioxide
include: refrigerant fluid, cooling agent, food packaging,
soldering and moldering agent, fumigant, anti-fire, additive to
beverages and water treatment. There have also been proposals for
use in synthetic chemistry, for example in production of urea, in
the Kolbe-Schmitt reaction to produce 4-hydroxybenzoic acid and as
an additive to carbon monoxide in the production of methanol.
[0003] U.S. Pat. No. 3,766,027 describes recovery of carbon dioxide
from the atmosphere with a chemical sorbent, removal of the
CO.sub.2 from the sorbent and regeneration of the sorbent by the
application of heat, and conversion of CO.sub.2 into methane by
reaction with hydrogen in an electrolysis methanation cell.
[0004] U.S. Patent Publication 2008/0115415 (Agrawal and Singh)
describes production of synthetic liquid hydrocarbon fuel from
carbon containing moieties such as biomass, coal, methane, naphtha
as a carbon source and hydrogen from a carbon-free energy source.
The biomass can be fed to a gasifier along with hydrogen, oxygen,
steam and recycled carbon dioxide. The synthesis gas from the
gasifier exhaust is sent to a liquid hydrocarbon conversion reactor
to form liquid hydrocarbon molecules. Unreacted CO and H.sub.2 can
be recycled to the gasifier along with CO.sub.2 from the liquid
hydrocarbon conversion reactor system. Hydrogen can be obtained
from electrolysis of water, thermo-chemical cycles or directly by
using energy from carbon-free energy sources. Rakesh Agrawal,
Navneet R. Singh, Fabio H. Ribeiro, and W. Nicholas Delgass in Proc
Natl Acad Sci USA. 2007 Mar. 20; 104(12): 4828-4833 describe a
proposal for a hybrid hydrogen-carbon (H.sub.2CAR) process for the
production of liquid hydrocarbon fuels wherein biomass is the
carbon source and hydrogen is supplied from carbon-free energy. To
implement this concept, a process has been designed to co-feed a
biomass gasifier with H.sub.2 and CO.sub.2 recycled from the
H.sub.2--CO to liquid conversion reactor. In a typical gasifier,
oxygen and steam are supplied along with a carbon-containing feed
stock. The resulting combustion energy not only provides heat for
the endothermic gasification reaction, a majority of which is
stored in the CO and H.sub.2 exiting the gasifier, but also
compensates for the energy losses from the system. CO.sub.2 is
formed in the gasifier from the combustion reaction and through the
water-gas shift (WGS) reaction in post-gasifier processing. Whereas
in the past it has been common to talk about the possibility of
sequestering the resulting CO.sub.2, the H.sub.2CAR process plans
to either suppress the formation of this CO.sub.2 or react it with
H.sub.2 from a carbon-free energy source such as solar, nuclear,
etc. to produce liquid fuel. The reverse WGS reaction of CO.sub.2
with H.sub.2 to form CO and H.sub.2O is an endothermic reaction and
requires high temperatures to obtain a reasonable conversion. To
simplify the overall process, the authors propose to recycle
CO.sub.2 from the H.sub.2--CO to liquid conversion processes (such
as a Fischer Tropsch process) to a suitable location in the
gasifier. Furthermore, to help drive the thermodynamic equilibrium
to the favorable H.sub.2/CO ratio of near two, the proposed process
directly feeds H.sub.2 from the carbon-free energy source to the
gasifier.
[0005] PCT Publication WO 2007/108014 describes a process for
producing high octane fuel from carbon dioxide and water. The
feedstock for the production line consists of highly concentrated
carbon dioxide, extracted as a waste product from industrial
processes, and water, which may be of lower quality. Water is
electrolyzed into hydrogen and oxygen. The end product can be high
octane gasoline, high cetane diesel or other liquid hydrocarbon
mixtures suitable for driving conventional combustion engines or
hydrocarbon suitable for further industrial processing or
commercial use. Products such as dimethyl ether or methanol may
also be withdrawn from the production line. The process is emission
free and reprocesses all hydrocarbons not suitable for liquid fuel
to form high octane products. The heat generated by exotheimic
reactions in the process is fully utilized as is the heat produced
in the reprocessing of hydrocarbons not suitable for liquid
fuel.
[0006] Oh-Shim Joo et al in Ind. Eng. Chem. Res., 38 (5), 1808
-1812, 1999 describe use of the reverse-water-gas-shift followed by
methanol synthesis reactor to form methanol from CO.sub.2
hydrogenation. Carbon dioxide was converted to CO and water by the
reverse-water-gas-shift reaction to remove water before methanol
was synthesized. Zinc oxide/alumina catalysts have been developed
for this reaction.
SUMMARY OF THE PRESENT INVENTION
[0007] The present invention provides a method by which renewable
energy sources are used to convert carbon dioxide existing in a
gaseous environment, including air, into useful materials,
including fuels such as gasoline, diesel fuel, jet fuel, heating
oil, methanol, ethanol, or other organic fuels.
[0008] The conversion process is accomplished by (1) extracting
carbon dioxide from a gaseous source using a sorbent such as sodium
hydroxide, calcium hydroxide, potassium hydroxide, etc.; (2)
utilizing wind power, solar power, hydroelectric power, or other
renewable energy sources to regenerate said sorbent by membrane
cell electrolysis or other similar method, simultaneously producing
hydrogen (H.sub.2) gas; and (3) utilizing the Fischer Tropsch
process, Mobil process, ICI process, concomittantly with or after
effecting the reverse water-gas shift reaction
CO.sub.2+H.sub.2<-->CO+H.sub.2O
to convert said CO.sub.2 and H.sub.2 gas into useful liquid
fuels.
DETAILED DESCRIPTION OF THE INVENTION
[0009] Specifically, the method of the present invention comprises
the combination of the steps described below. Each step is based on
well established, existing technology. However, the combination of
such steps to produce a new environmentally-friendly process for
recovery of carbon dioxide and its conversion into useful products
is new and provides a means for recycling the carbon dioxide
released by burning fuels in, for example, automobiles, trucks,
airplanes, and heavy equipment which will release an amount of
CO.sub.2 that is equal to the CO.sub.2 that was extracted from the
atmosphere by the invention.
[0010] The present invention can be used to effectively convert any
arbitrary fleet of CO.sub.2-producing engines into a carbon-neutral
system powered entirely by renewable energy, without the need to
re-engineer the existing fleet. By pairing an arbitrary fleet of
CO.sub.2-producing automobiles, trucks, etc. with a fuel production
plant of the appropriate capacity which uses the method described,
the combined system (consisting of the plant plus the fleet) is
rendered carbon neutral: the CO.sub.2 generated by the fleet is
completely offset by the CO.sub.2 absorbed in the production plant.
The energy used by the fleet is exactly equal to the energy
contained in the fuel produced by the plant. Since the fuel
produced by the plant is fungible with the fuel used by the fleet,
all the energy used by the combined system has effectively been
derived from renewable resources. In effect, the invention can be
used to convert any existing or future fleet of internal-combustion
automobiles, etc. into a carbon neutral system powered entirely by
renewable energy--thus obviating the necessity to re-engineer said
fleet to achieve reductions in CO.sub.2 emissions. Thus, the
invention is a cost-effective substitute for existing research into
fuel-cell vehicles, electric cars, etc. In addition, by relying on
domestic renewable resources such as wind and solar power, the
invention has the potential to replace imported fossil hydrocarbons
with domestic, synthetically produced, renewable hydrocarbons,
reducing or eliminating the reliance of the US on foreign imported
oil.
[0011] In one embodiment, the method consists of the following
steps, which are each performed simultaneously in a continuous loop
cycle. [0012] (1) Extracting CO.sub.2 from ambient air or other gas
stream. This can be effected by passively passing such air over a
CO.sub.2 sorbent, for example aqueous solutions of alkali metal or
alkaline earth metal hydroxides such as sodium hydroxide, potassium
hydroxide.
[0013] For example, using sodium hydroxide solution as the sorbent,
CO.sub.2 is absorbed in a reaction of the form:
CO.sub.2+2NaOH(aq).fwdarw.Na.sub.2CO.sub.3(aq)+H.sub.2O,
followed by
Na.sub.2CO.sub.3(aq)+CO.sub.2+H.sub.2O.DELTA.2NaHCO.sub.3
[0014] The carbon dioxide absorbed in this way may be regenerated
periodically on site or transported to a suitable location for
regeneration of carbon dioxide from that which has been absorbed at
a variety of locations.
[0015] Methods for effecting efficient removal of carbon dioxide
from the air include those developed by Klaus Lackner and his
colleagues, for example those described in PCT publications WO
2006/023743, WO 2006/036396, WO 2006/084008, WO 2006/113674, WO
2007/016271, and W02008/061210 and in U.S. Patent Publications
2006/0186562, and 2006/0289003, the subject matter of all of which
are incorporated herein by reference. Such methods may include
exposing solvent covered surfaces to air streams where the airflow
is kept laminar, or close to the laminar regime. Such methods may
involve use of an apparatus, which is a laminar scrubber,
comprising solvent covered surfaces situated such that they can be
exposed to air streams such that the airflow is dept laminar.
[0016] (2) Releasing said CO.sub.2 from the Na.sub.2CO.sub.3
solution by bubbling a gaseous halogen such as chlorine, through
the sodium bicarbonate solution produced in step (1), in accordance
with a reaction of the form:
[0016] Cl.sub.2+2OH.sup.-.fwdarw.Cl.sup.-+ClO.sup.-+H.sub.2O
Na.sup.++HCO.sub.3.sup.-+H.sup.++ClCO.sub.2+H.sub.2O+Na.sup.++Cl.sup.-
Or stated alternatively
NaHCO.sub.3(aq)(sodium bicarbonate)+HCl(aq)(hydrochloric
acid).fwdarw.CO.sub.2+NaCl(aq)+H.sub.2O(brine).
[0017] One such method is described in PCT Publication WO
2007/018558 (Columbia University), the contents of which are
incorporated herein by reference. [0018] (3) Regenerating said
sorbent by applying the membrane cell electrolysis process or other
comparable process to the brine solution (NaCl(aq)) in accordance
with a reaction of the form:
[0018] 2NaCl+2H.sub.2O.fwdarw.Cl.sub.2+2NaOH+H.sub.2
[0019] Said reaction requires the input of electric power in order
to proceed. Modem, large scale membrane cell electrolysis plants
are widely deployed throughout the world and are used for the
commercial production of NaOH and Cl.sub.2. A typical plant
producing 100,000 tonnes per annum of NaOH draws about 35 MW of
power, which is equivalent to approximately 3,000 kilowatt-hours
(kWh) per ton of NaOH produced. If desired and if multiple sorbent
locations are used, the regenerated sorbent can then be
redistributed to the sorber locations. [0020] (4) Converting
CO.sub.2 and H.sub.2 gas into fuels or other useful products
utilizing established, existing technologies.
[0021] Typically such conversion will be combined with or preceded
by at least a partial conversion of carbon dioxide to carbon
monoxide with a reaction with hydrogen to produce the desired
product. The conversion CO.sub.2 and H.sub.2 gas into liquid fuels
utilizes established, existing technologies. As noted above, the
reverse-water-gas-shift reaction may be employed to convert carbon
dioxide to carbon monoxide which can be used in a variety of
reactions to produce hydrocarbons.
[0022] Production of long-chain hydrocarbons such as high-cetane
diesel, jet fuel, or heating oil may be effected by use of the
Fischer Tropsch process by reaction of carbon monoxide and hydrogen
in the presence of a Fischer Tropsch catalyst. Conversion of carbon
dioxide via the water gas shift reaction into carbon monoxide for
use in this reaction is catalyzed by many (but not all) of the same
catalysts that promote F-T synthesis, in particular Fe catalyst and
other catalysts that contain Fe. The reaction proceeds
simultaneously with the main Fisher-Tropsch reaction inside the
reactor. In the Fischer-Tropsch reactor, an appropriate amount of
steam is introduced so that the stoichiometry results in the
production of the appropriate amount of H.sub.2 and the conversion
of the appropriate amount of CO.sub.2. Suitable FischerTropsch
catalysts are well known and include catalysts based on iron and
cobalt, although nickel and ruthenium have also been used. The
process was used by Germany in World War II to produce diesel fuel
from coal, and has been used in South Africa for the same purposes.
Virtually all of South Africa's liquid fuel needs are met by
various Fischer Tropsch plants operated by SASOL, the state-run oil
company.
[0023] As an alternative to proceeding directly from carbon oxides
to hydrocarbons, one can also react hydrogen and carbon oxides to
produce methanol. The methanol can then be utilized in various
industrial processes or for fuel, or it can be further converted to
hydrocarbons by known methods. Today, the most widely used catalyst
for the production of methanol is a mixture of copper, zinc oxide,
and alumina first used by ICI in 1966. At 5-10 MPa (50-100 atm) and
250.degree. C., it can catalyze the production of methanol from
carbon monoxide and hydrogen with high selectivity:
CO.sub.2+3H.sub.2.fwdarw.CH.sub.3OH+H.sub.2O
[0024] Other techniques for converting carbon dioxide directly to
methanol include the electrochemical method of U.S. Pat. No.
4,609,441, enzymatic conversion as described in PCT Publication
WO/2007/022504 and catalytic hydrogenation, for example as
described by Barrault and Urresta in Comptes Rendus de l'Academie
des Sciences Series IIC Chemistry, Volume 2, Number 3, March 1999,
pp. 167-174(8).
[0025] When gasoline is the desired product, this can be obtained
by use of the Mobil process using a ZSM-5 or similar catalyst.
Under two standard embodiments of the Mobil process, synthesis gas
(CO+H.sub.2) is first converted to either methanol, using
techniques described above, or to Fischer-Tropsch products using a
Fischer-Tropsch process. By taking advantage of the water gas shift
reaction described above
CO.sub.2+H.sub.2CO+H.sub.2O
and adjusting the stoichiometry of the reaction chamber
appropriately, either of the above processes can be made to proceed
using CO.sub.2 as feedstock in place of CO.
[0026] As a second step in the Mobil process, the resulting
methanol or Fischer-Tropsch products are reacted over a ZSM-5
catalyst. The reaction products are cooled, distilled, and
upgraded, resulting in a high octane gasoline.
[0027] Various catalysts for generating ethanol from
CO.sub.2/H.sub.2 gas have been proposed; however, none has been
deployed on a commercial scale. Methanol may be converted to a
hydrocarbon by known methods such as passage over a ZSM-5 catalyst
at high temperature, such as 350-450.degree. C.
* * * * *